I'm going to pick up my second Roadstar in a week and they're amazing. Lots of people say the best choice is 2005 and up. Those have the 1700cc engine and upgraded electrical system. Mine have both been 1600s though, and I'm plenty happy with the amount of power available from the pre-2004 models.
They're super easy to maintain, just be aware that the user manual calls for too much oil. Don't take my word for it...check out roadstarclinic.com. If you put 4.3 quarts in there when you change the oil, you WILL have oil overflowing into your air filter and sneezing all over the rear cylinder exhaust pipe. It's got a reservoir. 2 quarts synthetic, start it for 30 seconds (with dip stick inserted tightly), 2 more quarts. Go ride 5,000 miles. Repeat.
A low mileage bike is awesome, but it's hard to know if it sat early in its life, or if it has been sitting recently. The only thing you can be sure of is that the bike has done a lot of sitting. A lot of times on these bikes, "new tires" are actually "old tires with a lot of tread."
Pay special attention to the tread for any signs of dry rot. I like to take a good look down in the bottoms of the valleys of the tread. If you see any cracking, be wary. It's better to eat the $400 and replace questionable tires, than to find yourself wishing you had when things go dicey in a corner.
Other than that, you're looking into a very reliable bike. The hydraulic valves are self-adjusting. The manual calls for 15,000 mile valve adjustments, but I just read a forum thread started by a guy with 170,000 miles on his Roadstar who never adjusted them yet.
Also, don't worry too much about SVS unless something specifically leads you there. I was all worried about my head bearings and forum members said something to the effect of "Don't go looking for problems. You'll know if something is wrong."
Great bike. Great choice. Have fun!
Ben C - Cary, NC
2001 XV1600A Road Star
2003 XVS650A V Star Classic